10 FEBRUARY 1923, Page 41

The course of lectures embodied in this book was designed

equally for the student of philosophy and the cultured layman. Professor Keyser deals in a non-technical manner with the main fundamental concepts employed in the structure of mathematical thought, such as propositional function, mathematical transformation, group concept, variables, limits, and the new or completed infinity. The author's style, though rather laboured at times, is yet calculated to inspire enthusiasm in the amateur. For he discusses at length the relationship between mathematics, psychology, and the theory of knowledge ; and speculates in an interesting manner on probable future developments. No one who wishes to keep in touch with the new movements in philosophy can afford to miss this book.